I'll give you an example how much chalk can help.
We had a one arm deadlifting comp, no chalk, wraps or belt. Most of the strong guys maxed out at 100kg.
Then Albert asked if he could try with chalk, seeing he won the comp.
He pulled 150kg with one arm. I have a picture of this amazing feat, but posting on here is ridiculously awkward, compared to nissansilvia.com, thats why I dont post pics.
Anyway, thats how much difference chalk can make.
The quality of the knurling on the bar also plays a massive role. Most of the interstaters that fly to Melb to lift at my comps reckon the bars play a big role.
So if your pulling 140kg with sweaty hands on a crap bar, your not doing that bad.
I see your a car nut, so am I and so are 75% of my clients. Three are going on a road trip from QLD to Melb in a 180SX to lift at my comp, you could join them, but I see you have a youngun, maybe another time.